Dip Plaster of Paris strips in water and apply evenly to the top half of the basketball.
Immediately press bubble wrap to the surface to press "craters" into the model. Remove the bubble wrap in about a minute.
Allow the Plaster of Paris to dry, spraying lightly with water two or three times to slow down drying and prevent cracking.
Roll the basketball over, wet the Plaster of Paris strips and apply to the other half of the basketball.
Press bubble wrap into the Plaster of Paris and remove after one minute, and allow to dry, spraying lightly with water to slow down drying and prevent cracking.
Paint the model a light blue with watercolors to imitate the color of the dwarf planet and allow to dry. If the blue is too light, repeat the painting process.